CN110644481A - Radial variable modulus composite pile and construction equipment and construction method thereof - Google Patents

Abstract

The invention discloses a radial variable modulus composite pile and construction equipment and a construction method thereof. The invention is compounded by a multilayer structure with variable radial modulus, each layer is uniformly and completely stirred, and the stress ratio of the pile soil can be adjusted to a reasonable range, so that each component can fully exert respective effect, and the settlement design concept is embodied.

Description

A kind of radial variable modulus composite pile and its construction equipment and construction method

technical field

The invention relates to the technical field of composite foundations, in particular to a radially variable modulus composite pile and its construction equipment and construction method.

Background technique

The concept of composite foundation was formed in the 1960s, which means that part of the soil in the natural foundation is reinforced, or replaced, or reinforced materials are set in the natural foundation during the foundation treatment process. The artificial foundation composed of two parts, the improved natural foundation soil) and the reinforcement. Its theory is the basis for the analysis and design of many processing methods, such as gravel piles, sand piles, cement-soil mixing piles, rotary spray piles, plain concrete piles, CFG piles (cement fly ash gravel piles) and so on. The composite foundation has two basic characteristics: first, the reinforcement area is composed of the matrix and the reinforcement, which is heterogeneous and anisotropic; second, under the action of the load, the matrix and the reinforcement share the load. According to the direction of reinforcement in the foundation, it can be divided into horizontal reinforcement composite foundation and vertical reinforcement composite foundation. Vertically reinforced composite foundations are often referred to as pile-body composite foundations.

There are many types of pile-body composite foundation technologies. Among them, the cement-soil mixing pile technology is a commonly used and relatively economical soft soil foundation treatment technology. Stirring uses a series of physical and chemical reactions between the cement and the soil to increase the strength of the foundation soil, change the soil properties, and form a composite foundation with integrity, water stability and certain strength.

At present, the cement-soil mixing pile has become one of the most widely used foundation treatment technologies in my country, especially in the treatment of soft foundations, to increase the bearing capacity of the foundation, reduce the foundation settlement and uneven settlement, and improve the stability. In the past ten years, the technology of mud mixing piles has been further studied, improved and perfected at home and abroad. However, the statistical analysis of a large number of construction materials of cement mixing piles in recent years shows that the uneven mixing and incomplete forming of the pile body are the main reasons for the current softness. The outstanding quality of cement-soil mixing piles under soil foundation conditions is mainly due to insufficient mixing of soil and cement slurry between piles, uneven supply of cement slurry and other factors, resulting in the separation of cement and soil into lumps or a thousand-layer cake The shape, uniformity, integrity, strength and other quality indicators do not meet the design requirements. The uneven mixing, discontinuous pile body, low strength of the pile body, environmental pollution and waste of resources caused by the construction of slurry in the cement-soil mixing pile technology will directly lead to the unreliable pile quality of the cement-soil mixing pile. The amount is uncontrollable.

Therefore, it is necessary to develop a controllable and variable modulus composite pile.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a radially variable modulus composite pile in view of the above problems. The composite pile is composed of a multi-layer structure with variable radial modulus, and each layer is stirred evenly and completely, and the pile-soil stress ratio can be adjusted to a reasonable level. range, so that each component can give full play to their respective effects, reflecting the settlement design concept. Another object of the present invention is to provide construction equipment and construction method for radially variable modulus composite piles.

In order to achieve the above object, the technical scheme of the composite pile of the present invention is:

A radially variable modulus composite pile, comprising a cement mortar core column, a stirring cement mortar soil surrounding column and foundation soil sequentially arranged from the inside to the outside, and the agitating cement mortar soil surrounding column is fully stirred by the cement mortar and soft soil. to make.

Compared with the prior art, the beneficial effects of the composite pile of the present invention are:

The high-modulus cement mortar core column, the medium-modulus agitated cement mortar soil enclosure column and the low-modulus foundation soil of the present invention form a composite foundation with gradual radial modulus, all parts are uniform and complete, and the pile-soil stress ratio can be adjusted to The reasonable range enables each component to give full play to their respective effects, embodies the concept of design according to settlement, and greatly improves the quality and reliability of composite piles.

Preferably, a sprayed cement mortar soil enclosure is further provided between the stirring cement mortar soil enclosure and the foundation soil, and the sprayed cement mortar soil enclosure is formed by mixing the sprayed cement mortar and soft soil.

By adopting the above scheme, a sprayed cement mortar soil with a modulus between the two is added between the medium-modulus agitated cement mortar soil column and the low-modulus foundation soil, which further improves the controllability of the composite pile modulus. At the same time, the strength of the composite pile is improved.

The technical scheme of the composite pile construction equipment of the present invention is:

A construction equipment for a radially variable modulus composite pile, comprising an auger rod, a driving device for driving the auger rod, and a cement mortar pool, the auger rod is provided with a low-pressure passage through the inside, and the upper end of the low-pressure passage is The cement mortar pool is connected by a low-pressure pump, a low-pressure outlet is connected to the drill bit at the lower end, a plurality of stirring blade groups are arranged on the peripheral surface of the lower part of the auger rod, the stirring blades are hollow and are provided with a high-pressure cavity inside, and the stirring The bottom surface of the blade is provided with a high-pressure outlet communicating with the high-pressure chamber, and a high-pressure channel is arranged inside the auger rod. One end of the high-pressure channel is connected to the cement mortar pool through a high-pressure pump, and the other end is connected to the high-pressure chamber.

Compared with the prior art, the beneficial effects of the construction equipment of the present invention are:

The auger rod of the present invention is provided with a low-pressure channel and a high-pressure channel inside, a hollow stirring blade is arranged on the lower peripheral surface, and the low-pressure channel injects cement mortar into the drill hole when the auger rod is lifted to form the core column and the surrounding column;

The stirring blade of the present invention pre-mixes the surrounding foundation soil when the auger rod is drilling, and fully stirs the pre-stirred foundation soil and cement mortar when the auger rod is lifted to form a mixing cement mortar surrounding column with high uniformity, which greatly improves the surrounding column. Uniformity to ensure the strength and quality of composite piles;

The mixing blade of the present invention is provided with a high-pressure cavity connected with the high-pressure channel. When the auger rod is lifted, the cement mortar is ejected from the high-pressure outlet on the bottom surface of the mixing blade. Under the action of centrifugal force, the cement mortar is thrown out and mixed with the surrounding foundation soil to form Cement mortar soil enclosure columns are sprayed to quickly form composite pile structures.

Preferably, the stirring blade group is evenly distributed along the axial direction of the auger rod, and the stirring blade group includes two stirring blades at 180 degrees to each other, and the adjacent stirring blade groups are arranged relatively vertically.

By adopting the above solution, the mixing uniformity of the mixing blades is improved, and the injection uniformity of the cement mortar sprayed from the high-pressure outlet is ensured at the same time.

The technical scheme of the construction method of the composite pile of the present invention is:

A construction method of construction equipment for radially variable modulus composite piles, comprising the following steps:

S1, control the drilling of the auger rod to the design depth through the driving device, and the stirring blade pre-disturbs the surrounding soft soil;

S2. Control the lifting of the auger rod through the driving device, and control the operation of the low-pressure pump at the same time, the cement mortar is ejected from the low-pressure outlet, and the stirring blade performs secondary pre-agitation to the surrounding soft soil;

S3. Control the auger rod to re-drill through the driving device. During the drilling process, the auger rod squeezes the cement mortar injected in step S2 into the soft soil layer that has been fully agitated around it. Mixing to form a mixing cement mortar soil fence;

S4. Control the lifting of the auger rod through the driving device, and control the operation of the low-pressure pump at the same time, the cement mortar is ejected from the low-pressure outlet to form a cement mortar core column, and the stirring blade fully stirs the stirring cement mortar soil column .

Compared with the prior art, the beneficial effects of this construction method are:

The invention rapidly forms a composite pile structure by increasing the auger rod of the stirring blade, and fully stirs the foundation soil and the cement mortar during the construction process, which can ensure the uniformity of each layer and improve the overall strength;

In the present invention, the cement mortar for mixing the cement mortar soil surrounding column is squeezed by the auger rod into the foundation soil passing through the pre-stirring plate, which can ensure that it is fully mixed;

The construction method of the invention is simple, no other construction equipment is needed, the cost is low, the construction effect is good, and the popularity is strong.

Preferably, the step S2 further includes controlling the operation of the high-pressure pump, and the cement mortar is ejected from the high-pressure outlet on the bottom surface of the stirring blade, and is thrown out and mixed with the surrounding soft soil under the action of centrifugal force to form a cement mortar soil enclosure column.

Preferably, the step S4 further includes controlling the operation of the high-pressure pump, and the cement mortar is ejected from the high-pressure outlet on the bottom surface of the stirring blade, and is thrown out and mixed with the surrounding soft soil under the action of centrifugal force to form a cement mortar soil enclosure column.

By adopting the above scheme, when the auger pipe is lifted, the high-pressure pump controls the injection of cement mortar from the high-pressure outlet, and while the cement mortar is injected at a low pressure, a cement-mortar soil enclosure column is formed at the outermost periphery.

Description of drawings

In order to illustrate the specific embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that are required to be used in the description of the specific embodiments or the prior art. Similar elements or parts are generally identified by similar reference numerals throughout the drawings. In the drawings, each element or section is not necessarily drawn to actual scale.

FIG. 1 is a schematic structural diagram of a radially variable modulus composite pile according to an embodiment of the present invention.

2 is a schematic structural diagram of a construction equipment for a radially variable modulus composite pile according to an embodiment of the present invention.

Shown in the picture:

1. Cement mortar core column;

2. Mixing cement mortar soil fence;

3. Spray cement mortar soil fence;

4. Foundation soil;

5. Auger pipe; 501, low pressure channel; 502, low pressure outlet; 503, high pressure channel;

6. Cement mortar pool;

7. Stirring blade; 701, high pressure chamber; 702, high pressure outlet;

8. Low pressure pump;

9. High pressure pump.

Detailed ways

Embodiments of the technical solutions of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to more clearly illustrate the technical solutions of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the usual meanings understood by those skilled in the art to which the present invention belongs.

In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", " Rear, Left, Right, Vertical, Horizontal, Top, Bottom, Inner, Outer, Clockwise, Counterclockwise, Axial, The orientations or positional relationships indicated by "radial direction", "circumferential direction", etc. are based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the indicated devices or elements. It must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as a limitation of the present invention.

In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. In the description of the present invention, "plurality" means two or more, unless otherwise expressly and specifically defined.

In this application, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrated; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of the two elements or the interaction relationship between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In this application, unless otherwise expressly stated and defined, a first feature "on" or "under" a second feature may be in direct contact with the first and second features, or the first and second features indirectly through an intermediary touch. Also, the first feature being "above", "over" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

As shown in FIG. 1 , this embodiment provides a radially variable modulus composite pile, which includes a cement mortar core column 1 , a cement mortar soil enclosure column 2 and a foundation soil 4 , which are sequentially arranged from the inside to the outside. The soil enclosure column 2 is fully mixed with cement mortar and soft soil.

Between the mixing cement mortar soil enclosure column 2 and the foundation soil 4, a sprayed cement mortar soil enclosure column 3 is also provided, and the sprayed cement mortar soil enclosure column 3 is formed by mixing the sprayed cement mortar and soft soil.

The high-modulus cement mortar core column 1, the medium-modulus agitated cement mortar soil column 2 and the low-modulus foundation soil 4 form a composite foundation with gradual radial modulus, all parts are uniform and complete, and the pile-soil stress ratio can be adjusted In a reasonable range, each component can give full play to their respective effects, reflecting the concept of design according to settlement, and greatly improving the quality and reliability of composite piles.

Between the medium-modulus agitated cement mortar soil enclosing column 2 and the low-modulus foundation soil 4, a sprayed cement mortar soil with a modulus between the two is added, which further improves the controllability of the composite pile modulus, and at the same time improves the composite pile. the strength of the pile.

As shown in FIG. 2 , this embodiment also provides construction equipment for the above-mentioned radially variable modulus composite pile, including an auger rod 5 , a driving device for driving the auger rod 5 and a cement mortar pool 6 , and the interior of the auger rod 5 A low-pressure channel 501 is provided through, the upper end of the low-pressure channel 501 is connected to the cement mortar pool 6 through the low-pressure pump 8, and the lower end is connected to the drill bit with a low-pressure outlet 502. Among them, the driving equipment adopts a common foundation drilling machine, which is not shown in the figure.

The lower peripheral surface of the auger rod 5 is provided with a plurality of groups of stirring blades 7 , the stirring blades 7 are arranged in a hollow space, and a high pressure chamber 701 is arranged inside.

The bottom surface of the stirring blade 7 is provided with a high-pressure outlet 702 connected to the high-pressure chamber 701 , and a high-pressure channel 503 is arranged inside the auger rod 5 .

The 7 groups of stirring blades are evenly distributed along the axial direction of the auger rod 5, and the 7 groups of stirring blades include two stirring blades 7 at 180 degrees to each other, and the 7 groups of adjacent stirring blades are arranged relatively vertically to improve the stirring uniformity of the stirring blades 7, At the same time, the spray uniformity of the cement mortar sprayed from the high pressure outlet 702 is guaranteed.

A low-pressure channel 501 and a high-pressure channel 503 are arranged inside the auger rod 5, and a hollow stirring blade 7 is arranged on the lower peripheral surface. ;

The stirring blade 7 pre-mixes the surrounding foundation soil 4 when the auger rod 5 is drilling, and fully agitates the pre-stirred foundation soil 4 and the cement mortar when the auger rod 5 is lifted to form a high uniformity mixing cement mortar surrounding column, which greatly improves the Improve the uniformity of the perimeter column to ensure the strength and quality of the composite pile;

The inside of the stirring blade 7 is provided with a high-pressure cavity 701 that communicates with the high-pressure channel 503. When the auger rod 5 is lifted, the cement mortar is ejected from the high-pressure outlet 702 on the bottom surface of the stirring blade 7. The mixing of soil 4 can form a jet cement mortar soil enclosure column 3, thereby quickly forming a composite pile structure.

The present embodiment also provides a construction method for the above-mentioned radial variable modulus composite pile construction equipment, including the following steps:

S1, control the auger rod 5 to drill until the design depth through the foundation drilling machine, and the stirring blade 7 pre-disturbs the surrounding soft soil;

S2. Control the lifting of the auger rod 5 through the foundation drilling machine, and control the operation of the low-pressure pump 8 at the same time, the cement mortar is ejected from the low-pressure outlet 502, and the stirring blade 7 performs secondary pre-agitation to the surrounding soft soil;

S3. Control the auger rod 5 to drill again through the foundation drilling machine. During the drilling process, the auger rod 5 squeezes the cement mortar injected in step S2 into the surrounding soft soil layer that has been fully stirred, and is stirred by the stirring blade 7. Form a mixing cement mortar soil fence 2;

S4. The foundation drilling machine is used to control the lifting of the auger rod 5, and at the same time, the low-pressure pump 8 is controlled to work.

Preferably, the following operations can also be added to one or more of the above steps S2 and S4: the high-pressure pump 9 is controlled to work, the cement mortar is ejected from the high-pressure outlet 702 on the bottom surface of the stirring blade 7, and the cement mortar is thrown out and the periphery under the action of centrifugal force. The soft soil is mixed to form a jet cement mortar soil fence column 3 .

When the auger rod 5 is lifted, the high-pressure pump 9 controls the injection of cement mortar from the high-pressure outlet 702, and at the same time as the cement mortar is injected at a low pressure, a cement mortar soil enclosure 3 is formed at the outermost periphery.

The specific operating frequency of the high-pressure pump 9 is determined according to the actual design requirements.

In this embodiment, the composite pile structure is quickly formed by adding the auger rod 5 of the stirring blade 7, and the foundation soil 4 and the cement mortar are fully stirred during the construction process, which can ensure the uniformity of each layer and improve the overall strength;

In this embodiment, the cement mortar for stirring the cement mortar soil enclosure column 2 is squeezed by the auger rod 5 into the foundation soil 4 passing through the pre-stirring plate, which can ensure that it is fully mixed;

The construction method of this embodiment is simple, no other construction equipment is required, the cost is low, the construction effect is good, and the popularity is strong.

In the description of the present invention, numerous specific details are set forth. It will be understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

In the description of this specification, description with reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., mean specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples, without conflicting each other.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. The scope of the invention should be included in the scope of the claims and description of the present invention.

Claims (7)

1. a radially variable modulus composite pile, is characterized in that, comprises the cement mortar core column, the stirring cement mortar soil enclosure column and the foundation soil that are arranged successively from inside to outside, and the described stirring cement mortar soil enclosure column is made of cement mortar. Mix well with soft soil. 2 . A radially variable modulus composite pile according to claim 1 , wherein a jetting cement mortar soil surrounding column is further provided between the stirring cement mortar soil surrounding column and the foundation soil, and the spraying The cement mortar soil fence is composed of sprayed cement mortar mixed with soft soil. 3. A construction equipment for a radially variable modulus composite pile as claimed in claim 1 or 2, characterized in that it comprises an auger rod, a driving device for driving the auger rod and a cement mortar pool, The inside of the auger rod is provided with a low-pressure channel, the upper end of the low-pressure channel is connected to the cement mortar pool through a low-pressure pump, the lower end is connected to the drill bit and is provided with a low-pressure outlet, and the peripheral surface of the lower part of the auger rod is provided with a number of stirring blade groups, The stirring blade is hollow and is provided with a high-pressure cavity inside, the bottom surface of the stirring blade is provided with a high-pressure outlet that communicates with the high-pressure cavity, and a high-pressure channel is arranged inside the auger rod, and one end of the high-pressure channel passes through a high-pressure pump. The cement mortar pool is connected, and the other end is connected to the high pressure chamber. 4 . The construction equipment for a radially variable modulus composite pile according to claim 3 , wherein the stirring blade group is evenly distributed along the axial direction of the auger rod, and the stirring blade group includes a 180-degree angle to each other. 5 . The two stirring blades of different degrees are arranged relatively vertically adjacent to the stirring blade group. 5. a kind of construction method of the construction equipment of a kind of radial variable modulus composite pile as claimed in claim 3, is characterized in that, comprises the steps: S1, control the drilling of the auger rod to the design depth through the driving device, and the stirring blade pre-disturbs the surrounding soft soil; S2. Control the lifting of the auger rod through the driving device, and control the operation of the low-pressure pump at the same time, the cement mortar is ejected from the low-pressure outlet, and the stirring blade performs secondary pre-agitation to the surrounding soft soil; S3. Control the auger rod to re-drill through the driving device. During the drilling process, the auger rod squeezes the cement mortar injected in step S2 into the soft soil layer that has been fully agitated around it. Stir to form a stirring cement mortar soil fence; S4. Control the lifting of the auger rod through the driving device, and control the operation of the low-pressure pump at the same time, the cement mortar is ejected from the low-pressure outlet to form a cement mortar core column, and the stirring blade fully stirs the stirring cement mortar soil column . 6 . The construction method of a radially variable modulus composite pile construction equipment according to claim 5 , wherein the step S2 further comprises controlling the operation of the high-pressure pump, and the cement mortar is formed by the bottom surface of the stirring blade. 7 . The high-pressure outlet is ejected, and under the action of centrifugal force, it is thrown out and mixed with the surrounding soft soil to form a jet cement mortar soil column. 7 . The construction method of a radially variable modulus composite pile construction equipment according to claim 5 , wherein the step S4 further comprises controlling the operation of the high-pressure pump, and the cement mortar is formed by the bottom surface of the stirring blade. 8 . The high-pressure outlet is ejected, and under the action of centrifugal force, it is thrown out and mixed with the surrounding soft soil to form a jet cement mortar soil column.

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